(1) Field of the Invention
The present invention relates to a liquid crystal display device, and in particular, a display device which is appropriate for displaying videos.
(2) Related Art Statement
Display devices, particularly those for videos, can be roughly categorized into impulse response type display devices and hold response type display devices. Impulse response type display devices are display devices where the response of brightness lowers immediately after scanning, for example afterglow remains in cathode ray tubes, and cold response type display devices are such display devices as liquid crystal display devices which hold the brightness on the basis of display data until the next scan.
Hold response type display devices are characterized in that excellent display quality without flickering can be gained in the case of a still image but the outline of moving objects is blurry to the eye in the case of videos. That is to say, there is so-called video blurring, and thus, a problem arises, such that the display quality significantly lowers.
The cause of this video blurring is a so-called afterimage which remains on the retina, where the viewer interpolates the displayed image before and after the movement of the display image of which the brightness is held when moving the line of sight together with the moving object, and therefore, video blurring does not completely disappear, no matter how much the response rate of the display device is increased.
Methods for intermittently turning on the backlight in order to solve this problem are known. As one method for intermittently turning on the backlight, a method for driving scan-back light according to which the backlight is divided into a number of regions so that the divided regions can be turned on in sequence is known (see Patent Document 2 below).
Meanwhile, a method for simultaneously driving two screens according to which the liquid crystal display panel is divided in two and the respective liquid crystal display panels on the top and bottom are simultaneously driven in order to compensate for the lack of write-in information due to the high resolution of the liquid crystal display panel, or in order to drive the liquid crystal display panel as fast as 120 Hz (see Patent Document 1 below).
Here, the following prior art documents relate to the present invention.    (Patent Document 1) Japanese Unexamined Patent Publication 2002-372956 (Corresponding U.S. Application US2003/0043097 A1)    (Patent Document 2) Japanese Unexamined Patent Publication 2007-123233 (Corresponding U.S. Application US2007/0097288 A1)